user
Given two strings, check whether one string is a rotation of another?

Input: s1 = ‘waterbottle’
s2 = ‘erbottlewat’

Output:
assistant
def isRotation(s1, s2):
    if len(s1) != len(s2):
        return False

    s3 = s1 + s1 
    return s3.find(s2) != -1